Welding together two or more components in structural applications is a common occurrence that requires the weld line to have a substantial amount of strength. Typically the components being welded together are made from the same materials; however, with the increase in the use of plastics in manufacturing, often different types of plastics and/or metals or other materials are welded together forming a joint. In order to form strong joints, traditional adhesive bonding systems have been used. Traditional adhesive bonding systems involve placing an adhesive between the two components that are to be welded together and then heating the adhesive area to cause the adhesive to activate and form a joint between the two parts. Heat activated adhesives are traditionally activated by heating the area of the adhesive and weld line area from the outside inward using hot air or steam. Some adhesive systems have been developed that rely on microwave or UV light in order to put enough energy into the adhesive to activate the adhesive and form a welded joint. All of these systems require a large amount of heat, fixtures for manufacturing and requires significant amounts of time in order to form joints.
One particular system for welding of thermoplastic components involves what is commonly referred to as resistive implant welding (RIW). RIW involves placing a conductor, sometimes a metal conductor, between two thermoplastic components being welded together. The conductor is then heated causing the surface of each of the thermoplastic components to melt together to form a weld line at the joint. RIW technology has been used for forming welds between thermoplastic components. Conventional RIW technology has never been used to form welds between components that are not capable of melting together. There is a need to develop a hybrid RIW adhesive system that allows energy to be introduced into the adhesive from the inside out and allows for energy to be localized within the weld line. Additionally, it is advantageous to develop a RIW adhesive system that allows for two components being made of thermoplastic, thermoset, metal, glass, wood or virtually any other type of material and combinations thereof to effectively bond together two components and achieve a high degree of weld strength.
There further exists a need to develop adhesive systems that require less energy, fixtures and can still use traditional adhesive compounds. It is also desirable to develop an adhesive system that can be used in a variety of structural applications that include, but are not limited to, the forming of automotive components such as tailgates, doors, hoods, lids, semi-truck components including sleeper cab assemblies, marine and rail car applications that include the forming floor components, trailer floor components, heating and cooling trays for homes, and other housing applications such as doors and plumbing components including showers, sinks, wash basins, etc.